CN1209357C

CN1209357C - Tea polyphenols extracting process

Info

Publication number: CN1209357C
Application number: CNB03135467XA
Authority: CN
Inventors: 黄明; 张松波; 张守政; 冯政; 史绍林; 付金祥; 何跃飞; 高毅; 唐庆龙
Original assignee: RED-RIVER TANGREN BIOLOGY DEVELOPMENT Co Ltd
Current assignee: RED-RIVER TANGREN BIOLOGY DEVELOPMENT Co Ltd
Priority date: 2003-07-21
Filing date: 2003-07-21
Publication date: 2005-07-06
Anticipated expiration: 2023-07-21
Also published as: CN1482126A

Abstract

The present invention relates to an extraction method of theapolyphenols. The method comprises the steps that powdery tea extracting object is obtained by the steps of tea leaching, rough filtration of tea water, pectin removing by ultrafiltration, dehydrating concentration by sodium filtration or reverse osmosis, vacuum concentration and spray drying, theobromine is the powdery tea extracting object is eliminated and the tea polyphenol is extracted by carbon dioxide supercutical fluid, the powdery tea extracting object is dissolved by the deionized water, and the high-purity tea polyphenol is obtained by the extraction ethyl acetate and the spray drying of exsolution. Product purity is larger than 98%, an extraction rate is larger than 10%, and theobromine is less than 0.1%. The tea polyphenol extracted by the method of the present invention has the advantage of strong antioxidation, and is particularly suitable for the application of food, health care and medicine. Meanwhile, an efficient path is provided for the comprehensive utilization of middle and inferior tea in China.

Description

The extracting method of tea-polyphenol

Technical field

The present invention relates to a kind of extracting method of tea-polyphenol.

Background technology

As everyone knows, have the function of anti-oxidant, anti-ageing, radioprotective, antitumor, sterilization and disinfection and raising body immunity in the tealeaves based on the tea-polyphenol (GTP) of catechin, it has been widely used in medicine, health care and food service industry.According to domestic and international publication, the method for extracting tea-polyphenol from tealeaves has: ion precipitation method, solvent extration, resin adsorption method and supercritical carbon dioxide extraction method etc.The present all shortcomings of various degrees of aforesaid method, as: ion precipitation method yield is low, corresponding cost height; The product of solvent extration exists organic solvent residue; Resin adsorption method technology is loaded down with trivial details, and cost is also high, is difficult to large-scale production; Supercritical CO ₂The fluid extraction method still lacks the maturity of technology and reliability at present, awaits further Depth Study.

Summary of the invention

The purpose of this invention is to provide the extracting method of the tea-polyphenol of a kind of supercutical fluid and solvent extraction combination, it has the product purity height, the yield height, and energy consumption is low, no solvent residue, method is simple, adapts to mass-producing and automatic production.

The object of the present invention is achieved like this: the extracting method of this tea-polyphenol comprises: the tealeaves lixiviate, the tea coarse filtration, pectin is taken off in ultrafiltration, nanofiltration or reverse osmosis dehydration concentrate, make powdery tea through the atomizer drying and carry thing, under Co 2 supercritical fluid pressure 25-30Mpa, temperature 35-50 ℃, with water is secondary solvent, separate and resolve pressure 5-6Mpa decompression separation, removing powdery tea carries the trimethyl-xanthine in the thing and extracts tea-polyphenol, the deionized water dissolution extraction obtains the tea-polyphenol slurries, and ethyl acetate extraction makes purity greater than 98% tea-polyphenol through the precipitation spraying drying.

The extracting method of this tea-polyphenol comprises: the tealeaves lixiviate, the cooling coarse filtration, ultra-filtration membrane with molecular weight cut off 5～80,000 removes pectin, reverse osmosis membrane with molecular weight cut off 50～1,000,000 concentrates 8-10 doubly with tea, after spray-dried, at Co 2 supercritical fluid pressure 25-30Mpa, under temperature 35-50 ℃, with water is secondary solvent, static extracting 60 minutes, resolve pressure 5-6Mpa decompression separation to separate under the same temperature, vacuum-drying gets purity greater than 92% trimethyl-xanthine, the tea of caffein-free is carried thing uses Co 2 supercritical fluid at pressure 30-32Mpa, under temperature 35-50 ℃, with the aquifer ethyl is secondary solvent, cycling extraction 6-8 hour, decompression separation went out tea-polyphenol under the same temperature, with 10 times deionized water dissolved dilution, use the ethyl acetate extraction of volume ratio 1: 1.2-1.3 refining again, extraction phase is through precipitation, spraying drying makes purity greater than 98% tea-polyphenol.

The present invention has following advantage:

1, takes off pectin with ultrafiltration, to improve the tea-polyphenol quality product;

2, concentrate with nanofiltration or reverse osmosis dehydration, the catechin sex change loss of minimizing thermo-sensitivity also cuts down the consumption of energy;

3, use the Co 2 supercritical fluid caffein-free, can significantly reduce consumption of organic solvent, avoid hazardous solvent residual of product, use the co_2 supercritical fluid extraction tea-polyphenol, can improve product purity and improve ester catechin content.

4, tea-polyphenol product purity height (＞98%), yield height (＞10%), caffeine content low (＜0.1%);

5, technology is simple, can adapt to industrialization and automatic production.

Description of drawings

The present invention is further described below in conjunction with drawings and Examples.

Fig. 1 is a process flow sheet of the present invention.

The embodiment of the inventive method below is described.

Embodiment

Among Fig. 1, take by weighing 2000 gram low and middle-grade green tea or tea dusts, adds 20 liters of 90 ℃ of hot water, constant temperature stirring and leaching 30 minutes is crossed the filtering tea grounds, cools off below the tea to 40 ℃.Repeat lixiviate once, merge twice lixiviate tea through 120 order filter clothes filter 36.2 liters of tea, ultra-filtration membrane with molecular weight cut off 5～80,000 is removed pectin, with the dehydration of the reverse osmosis membrane of molecular weight cut off 50～1,000,000 concentrate 3.6 liters of strong tea water, spray-dried 320.8 gram powdery tea be carried thing, and powdery tea is carried thing, and to insert volume be that 5 liters supercritical extraction device inner edge feeds aqueous CO ₂The limit is warming up to 50 ℃ of constant temperature, is forced into 25～30Mpa, and static extracting 60 minutes is opened reducing valve, makes the CO that contains trimethyl-xanthine ₂Fluid step-down (Ps) is 5-6Mpa, isolates lurid pulpous state trimethyl-xanthine, gas CO in resolving separator ₂Recycle through strainer to high-pressure pump, the pulpous state trimethyl-xanthine gets 36.8 gram ground coffee alkali with vacuum-drying, purity 92.6%, is secondary solvent with the co_2 supercritical fluid extraction tea-polyphenol with 70% aquifer ethyl with the tea extract of caffein-free, 30-32Mpa is pressed in pressure (Pc) control, 35-50 ℃ of temperature (Tc), and static extracting is after 60 minutes, open reducing valve, make the CO that contains tea-polyphenol ₂Fluid step-down (Ps) is 5-6.5Mpa, isolates lurid tea-polyphenol slurries in separating separator, CO ₂The cycling extraction time is 6-8 hour, with of the deionized water dissolving of tea-polyphenol slurries with 2800 milliliters, it with volume ratio 1: 1.2 the continuous dynamic extraction of ethyl acetate three times, merge extraction phase, ethyl acetate is reclaimed in vacuum distilling, spraying drying makes elaboration tea-polyphenol 236.6 grams, purity 98.2%, yield 11.83% again.

Claims

1. the extracting method of a tea-polyphenol, it is characterized in that this method comprises: the tealeaves lixiviate, the tea coarse filtration, pectin is taken off in ultrafiltration, nanofiltration or reverse osmosis dehydration concentrate, make powdery tea through the atomizer drying and carry thing, under Co 2 supercritical fluid pressure 25-30Mpa, temperature 35-50 ℃, with water is secondary solvent, separate and resolve pressure 5-6Mpa decompression separation, remove powdery tea and carry the trimethyl-xanthine in the thing and extract tea-polyphenol, the deionized water dissolution extraction obtains the tea-polyphenol slurries, ethyl acetate extraction makes purity greater than 98% tea-polyphenol through the precipitation spraying drying.

2. the extracting method of tea-polyphenol as claimed in claim 1, it is characterized in that described method comprises: the tealeaves lixiviate, the cooling coarse filtration, ultra-filtration membrane with molecular weight cut off 5～80,000 removes pectin, reverse osmosis membrane with molecular weight cut off 50～1,000,000 concentrates 8-10 doubly with tea, after spray-dried, at Co 2 supercritical fluid pressure 25-30Mpa, under temperature 35-50 ℃, with water is secondary solvent, static extracting 60 minutes, resolve pressure 5-6Mpa decompression separation to separate under the same temperature, vacuum-drying gets purity greater than 92% trimethyl-xanthine, the tea of caffein-free is carried thing uses Co 2 supercritical fluid at pressure 30-32Mpa, under temperature 35-50 ℃, be secondary solvent with the aquifer ethyl, cycling extraction 6-8 hour, decompression separation goes out tea-polyphenol under the same temperature, with 10 times deionized water dissolved dilution, use the ethyl acetate extraction of volume ratio 1: 1.2-1.3 refining again, extraction phase is through precipitation, spraying drying makes purity greater than 98% tea-polyphenol.